Owning one rental outright vs two rentals with a mortgage.

[Marc Appel]

I bought my first home last year at the young age of 32. I am hoping to fix it up and rent it out by the end of this year. I am very new to understanding property investments. So happy to have found Bigger Pockets and all 

I have a "quick" investment scenario question that may be a long answer. 

Say I had 400K to spend and just wanted to build my rental portfolio. Would you gain more by buying one 400K home and renting it without a mortgage or two 400K homes with 200K down on each and 200k mortgage on each? Would that be a 10 or 15 yr mortgage to get lower interest. Would you want to put down 300K on one and save the other 100k till you get enough for another home?

Thanks for your time,

Marc